What would "additional confirmation" look like?

Are audio/video recordings I take with my phone going to be useless in a decade because deepfakes are virtually indistinguishable and there is no "additional confirmation"?

That is a good question, because there are two trends at play here. On the one hand, you have ever improving ability to create deepfake images, videos or audio recordings. On the other hand, AI-based retouching of photos and videos is now pretty much standard on mobile, some of it done by default and hidden from you in software. It wouldn't surprise me if the same was case with voice too.

Point being, it'll take more than just looking at the source image/video/audio for signs of AI manipulation, because soon enough, all recordings will be AI-manipulated before even hitting persistent storage.

In other words: everything will be deepfake by default, and the issue will turn into telling which deepfakes were done to lie about substantial aspects of reality pertinent to the case, and which ones were made to enhance some non-relevant qualities (aesthetics, compressibility, etc.).

Useless? No. Possibly open to being faked? Yes.

Lots of ways to sign photos and videos today that should make them fully verifiable in the future (assuming public/private key cryptography remains secure). For stuff that isn't signed, it's not like good old detective work can't verify in a lot of cases. Phone records, eye witnesses, additional unpublished recordings, etc.

Also being verified really only matters when it comes to "truth" as defined by law. It's not like your family won't enjoy your videos of Christmas '23.

a cryptographically-verified video of a phone taking a video of a screen playing another (fake) video, is not very useful though.

Additional confirmation could simply be multiple sources reporting the same thing. Once is circumstantial, but if 10 people record something from different perspectives then it is highly likely to be real.